1. College of Life Sciences, Capital Normal University, Beijing 100037, People's Republic of China
2. Beijing Key Laboratory for Resources Environment and Geography Information System, College of Resources Environment and Tourism, Capital Normal University, Beijing 100037, People's Republic of China
3. Agricultural Culture Collection Center of China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100080, People's Republic of China
4. College of Life Sciences, Hebei University, Baoding 071002, People's Republic of China